I was reading Eloquent JS and came across this code which didn't make sense to me. I wasn't able to understand it as it was explained and was hoping someone could explain to me why the second console.log evaluates to the value it does.
Here's the code:
var listOfNumbers = [2, 3, 5, 7, 11];
console.log(listOfNumbers[1]);
// → 3
console.log(listOfNumbers[1 - 1]);
// → 2
Any ideas?
2 is the first number in the zero-indexed array
listOfNumbers[1 - 1] = listOfNumbers[0] = 2
listNumber is an array containing 2, 3, 5, 7, 11
listNumber[0] is 2
listNumber[1] is 3
listNumber[2] is 5
listNumber[3] is 7
listNumber[4] is 11
listNumber[1-1] => listNumber[0] => 2
console.log(listNumber[0]); //will print 2 at console
arrays are 0 indexed. so list[0] = 2, list[1] = 3
[0] is the first element in an array. [1] is the second. Array indexes start with 0.
listOfNumbers[1 - 1]is the same aslistOfNumbers[0]